Incandescing electric lamp



.(No Model.) I

J. s. KELSO, J 1'.

INGANDESGING ELECTRIC LAMP.

No. 278,366. Patented Mar. 6,1 883.

A fig; 1 8

Q WITNESSES: k

.0" I 4 E I ATTORNEY i v v UNITE STATES PATENT FFICE.

JOHN S. KELSO,-JR., OF STAMFORD, CONNECTICUT.

INCANDESCING ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 273,366, dated March 6,1883.

Application filed October 11, 1882. (No model.)

To all whom it may concern.-

Be it known that I, JOHN S. KELSO, Jr., a citizen of the United States,residing at Stamford, in the county of Fairfield and State ofConnecticut, have invented new and useful Improvements in ElectricLamps, of which the following is a specification.

My invention relates to improvements in the manufacture of that class ofelectric lamps in which an electric current is caused to pass throughand heat a carbon fiber or filament 'forming part of the circuit, andwhich carbon fiber or filament is inclosed in a glass tube or globe fromwhich the air is exhausted, so as to form a vacuum; or the tube orglobeis filled with an artificial atmosphere. 7

My invention consists in so arranging two or more carbon fibers orfilaments or their equivalents upon a support, either divided orinsulated centrally. The carbons or filaments are mounted in such mannerthat so long as the main or first carbon remains perfect that carbonalone shall become incandescentybut immediately the said first or maincarbon or filament breaks or failsthe current shall be automatically andinstantaneously caused to pass through and cause another carbon, carbonfiber or filamentto become incandescent. Any number of carbons maybe'brought into operation in succession.

Oarbons or carbon filaments arranged according to my invention may beemployed in any desired-form or construction of incandescent lamp and-inany known systems of incandescent lighting byelectricity.

The accompanying drawings form part of this specification andillustratewhat I consider the best means of carrying out my invention.

Figure l is a side view of a pair of carbons or filaments mounted upon abase or support according to my invention. Fig. 2 is a similar sideView, showing the main or first carbon broken and the current passingthrough a secondary carbon. Fig. 3 is a side view, showing a slightmodification of my invention. Fig. 4 is a similar view, representingthree carbons or carbon filaments mounted and arranged to act insuccession. Fig. 5 is a modification of Fig. 4.

In each of the views similar letters of reference are employed toindicate corresponding parts wherever they occur.

A represents the main carbon or filament, and B a secondary carbon orfilament, of which there may be any desired number adapted forconsecutive operation as the prior carbons or filaments become broken orfail. The opposite ends, a a, of the carbon A are supported in socketsor clamps c 0, formed on or affixed to the opposite ends of a dividedsupport, which is by preference formed of bent wire arranged -in'twoparts or sections, 0 O, which are supported respectively by wires D D,formed by preference of platinum, and sealed or otherwise supported inthe globe or tube of the lamp. The wires D D are connected in theordinary manner, by wiresdd,with an electricapparatus. The oppositeends, I) I), of the carbon or filament B are supported in sockets orclamps c 0 formed on or affixed respectively to the inner ends of thewires forming the divided support 0 U. The divided support in thepresent instance is supposed to be formed of Germansilver wire, asufficient length of which is coiled up, as shown, to .form the sections0 C,

to insure that said sections 0 0 shall have a greater resistance to thepassage of electricity, when heated by the passage of a current ofelectricity therethrough, than the resistance offered by the carbon orfilament A when heated and rendered incandescent by the passage of thesaid current.

The end a. of the carbonA is mounted on the section'O in a position suchthat there shall be a'direct line of current from the wires (1 D, in thedirection of the arrows l 1, directly across the half-support (J, andthence up through the carbon A and around to the point.

of, when it will cross the section 0 and be conducted away by the wiresD d so long as the carbon A remains perfect, as shown in Fig. 1; butimmediately the carbon A breaks, as represented at A in Fig. 2, thecurrent, nolonger being able to pass the point A, willbe diverted andpass immediately and automatically from the wires d D along the wire ofthe coil forming the section C in the direction of the arrows 22 in Fig.2, and thence up and through the carbon B, thereby rendering itincandescent. The current will then pass through the wire of the coil'forming the section 0 and out by the wires D d, as before.

'The wires forming the sections of the divided support must be providedwith an insulated coating or covering, as will be well un- .derstood.

In Fig. 3 I have shown a slight modification in the arrangement of thecoils forming the sections of the divided support 0 0; but in otherrespects the description given in respect of Figs. 1 and 2 will apply tothis figure.

Fig. 4 is an illustration of my invention, in which three carbons, A, B,and 13*, are employed, mounted upon a support formed in 'four sections,0 G 0* 0, each composed ofa coil of wire, the cod of wire of thesections 0 and 0 being of a resistance similar to the resistance of thesections 0 (.l' in Figs. 1 and 2, while the sections 0* G* should beformed of a coil of wire'ot' a length sufficient to ofier a greaterresistance, by preference double that of the sections 0 0, the objectbeing to prevent the current passing to and rendering the carbon Bincandesceutuntilbothofthecarbous A and B have broken. This may beefl'ected by dropping the coils of the section 0* 0, as shown, or bycoilina a greater quantity of wire into thesections (3* G or by reducingthe diameter of the wire. a

In arranging a series of carbons, A B 13*, upon a divided support, 0 C0* 0, I prefer to arrange the resistance of the sections in suchrelation to the resistance of the carbon connected with the respectivepairs of sections thattbe said respective pairs of sections, whenheated, shall have a resistance greater than the resistance of thepreceding carbon. In proportion as the resistance of the pairs ofsections 0 C (3* 0* is increased the resistance of the carbons B B isdecreased. This is effected, by preference, by increasing the diameterof the cross-section of the carbon. This arrangement of the resistanceof the carbons enables me to obtain a uniform amount of light from therespective carbons.

Fig. 5 showsa modification of my invention in which the support for thecarbons is formed of a series of sections, 0 0' 0* 0 C U' insulated onefrom the other, as shown at z z, the sections 0 and 0* and C and 0,respectively, being connected together by a bent wire or coil, Y Y,while the sections 0* C and 0 and G are connected by an elongated coil,X X, as shown. In other respects the construction and operation of thedevice 1s similar to that shown and, described in relation to theprevious figures.

In fitting up a lamp according to myinvention care must be taken toascertain by means of the galvanometer the resistance of the direct orfirst cal hens. and o! the successive carbuns in relation to theresistance of the sections of the support by which they are carried.

Havingthus described myinvention, I would haveit understood that I donot claim, broadly, the arrangement of two or more carbons or filamentsor their equivalents on a support \byithin the globe or tube of anelectric lamp;

What I do claim, and desire to secure by Letters Patent, is-- 1. In anelectric lamp, the combination of two or more carbons, carbon filaments,or their equivalents upon a divided or insulated support, the resistanceof thedivided or insulated support, when heated, being greater than theresistance of the first or primary carbon, substantially as and for thepurpose described.

2'. In an electric lamp. two or more carbons supported on the oppositeends of the sections of a divided or insulated support, 0 O, havin g aresistance greater than that of the exterior or primary carbon,substantially as shown an d described.

3. In an electric lamp, the combination of two or more carbons orlight-giving, bodies, arranged within a globe or tube, inconnectiou witha divided or insulated support, 0 O, the sections of which have aresistance, when heated, higher than the resistance of one of thecarbons or light-giving bodies with which it is connected, substantiallyas and for the pur pose described.

4:. In an electric lamp, the combination 'of two or more carbons orlight-giving bodies, arranged within a globe or tube, in connection witha divided or insulated support, the sec tions of which are connectedtogetherin pairs by wires or equivalent conductors, having a resistance,when heated, higher than the resistance of one or the carbons orlight-giving, bodies supported or connected with the said pairs ofsections of the divided or insulated support, substantially as and forthe purposedescribed.

In witness whereof I have hereunto set my hand this 13th day ofSeptember, 1882.

JOHN S. KELSO, JR. Witnesses WM. HUToHrsoN, W. COLBORNE BROOKES.

